(a) Field of the Invention
The present invention relates to a system and a method for starting control of a hybrid vehicle which secures robust drivability when the hybrid vehicle starts.
(b) Description of the Related Art
A manual transmission vehicle is provided with various types of clutches (dry type/wet type). The clutches are mounted between an engine and a transmission so as to selectively transmit an engine output torque to the transmission.
When the manual transmission vehicle is started, a driver handles a clutch pedal and an accelerator pedal and controls the engine output torque so as to be supplied as a transmission input torque.
A clutch slip control is performed in an initial starting of the vehicle. The clutch slip control permits the vehicle to be started, reduces shock, jerk, or clutch judder which can occur when starting so as to provide a smooth starting, and prevents stall according to an urgent engine load.
An automatic transmission is provided with a torque converter instead of the clutch. The torque converter can increase the torque transmitted though a fluid-coupling but has a low transmitting efficiency. Therefore, fuel efficiency may be deteriorated.
Recently, because of demands for enhancement of fuel efficiency and reinforcement of exhaust gas regulations, eco-friendly vehicles have been researched. A hybrid vehicle is one type of such eco-friendly vehicles and attracts public attention.
The hybrid vehicle uses an engine and a motor as power sources, and enhances energy efficiency and reduces exhaust gas by selectively using the engine and the motor as the power sources.
In order to minimize cost and torque loss, a clutch operated by fluid, instead of a torque converter, is mounted between the engine and the motor in the hybrid vehicle.
The clutch mounted in the hybrid vehicle connects or disconnects the engine and the motor according to a driving condition such that torque transmitted to the transmission is optimized.
However, if the clutch slip control is not performed stably when connecting the engine with the motor, stall, drop, or flare may occur by overload of the engine. Accordingly, starting shock may occur.
In addition, since the clutch slip is not constant, robust drivability cannot be secured in a repetitive starting mode, and an excessive clutch slip causes clutch judder. Therefore, drivability may be deteriorated.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.